The present invention resides in the field of mechanical engineering, in particular precision engineering, and relates to rotors for fluid pumps.
Rotary pumps are common knowledge but these are constantly being improved, in particular for special applications. Thus axial pumps have become known which have a rotor conveying fluid in the axial direction in a housing, rotor and housing being deformable, advantageously compressible, in order to bring these before operation to a desired place of use which is difficult to access and in order to decompress and operate them there.
Such pumps are used for example in medicine in microconstruction form in order to be introduced into the body of a patient, for example via the bloodstream, and to be operated there either in a blood vessel or in a ventricle.
The pumps can be compressed such that they can be pushed through the blood vessel and then possibly decompressed in a larger body cavity in order to bring the rotor to unfold and to achieve a high conveying power.
A compressible rotor is known for example from U.S. Pat. No. 6,860,713.
Another rotor is known from U.S. Pat. No. 7,393,181 B2. The known solutions are based either on the elasticity and deformability of the material of the rotor or on mechanical constructions, such as the provision of bent places or joints for folding and unfolding the individual components.
Such constructions often have the disadvantage that the compressibility is limited since for example the hub of a rotor remains unchanged, that complex joints must be provided which are stabilised during operation and that partially super-elastic materials are used, such as memory alloys which change their shape as a function of the ambient temperature.
These constructions often make the use of composite materials necessary, and it is difficult, during construction of support constructions, not to impede the flow of the fluid to be conveyed and possibly to preclude as far as possible also damage to the fluid. This is important in particular when conveying blood which contains highly functional and also mechanically susceptible components.